Surface plasmon polaritons are spatially confined electromagnetic field modes at a metal-dielectric interface generating ultrashort and intense optical fields, which can potentially be used to enhance the optical response of quantum emitters. Consequently, the optical responses of hybrid nanostructures comprising active materials, e.g., semiconductors or layers and metals is currently attracting considerable attention. In this talk, some aspects of the fundamental physical mechanism in active plasmonics, namely the SPP-quantum emitter dipole coupling probed using various spectroscopy techniques will be explored.